1. Field of the Invention
This invention relates to improved microporous waterproof and moisture vapor permeable structures, and more particularly it relates to such structures which primarily comprise known microporous polytetrafluoroethylene (PTFE) or microporous interpenetrating matrices of PTFE and polydiorganosiloxane, and which have been treated in accordance with the process of this invention with either a curable or a non-curable hydrophobic silicone composition, or mixtures thereof, to produce microporous waterproof and moisture vapor permeable structures having improved physical characteristics and having resistance to surfactant activity.